Film-Tech Forum ARCHIVE: Speaker placement in a small auditorium

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Posted by Edgar Prass (Member # 7558) on 01-16-2014, 03:02 AM:

Greetings,

Currently I'm in the progress on planning the setup for our small auditorium in our art-house theatre. Room itself is about 6,4 x 9 x 4 meters (width, length, height). So the first row (5 rows total) would be seated about 4 meters from the screen making perforations in a perforated screen well visible. Would love to go for a full-width common-height screen to take the most visible screen are out of this room. Having a non-perforated screen and no extra space on the sides is the problem I'm facing. Would like some advice from you.
a) Install two sets on speakers. Left, center and right below the screen and another set above the screen?
b) Leave some space on the sides for narrow speakers and place center speaker above (and below?) the screen?
c) Some other that I'm not aware of?
Sorry for poor English, not a native speaker of English.

Posted by Marcel Birgelen (Member # 6801) on 01-16-2014, 03:54 AM:

Why not go for a MicroPerf screen? The perforations should only be visible up to about 3,7m / 12 ft and you can put the speakers neatly behind the screen instead of below, above and besides.

Many smaller rooms should rather be using MicroPerf screens...

Posted by Edgar Prass (Member # 7558) on 01-16-2014, 05:09 AM:

Yes, of course, microperforations are an option, but that would mean, that the screen would have to be even closer to the audience to accomodate speakers behind it. With room being that small I would prefer to have the screen as close to wall as possible to maximize the seating area.

Posted by Antti Nayha (Member # 4980) on 01-16-2014, 06:54 AM:

quote: Edgar Prass
a) Install two sets on speakers. Left, center and right below the screen and another set above the screen?

I'm not sure if two sets are worth it. A major chain around here likes non-perforated screens, so they simply install one set of three front speakers above the screen in all their new rooms. It kind of works, but particularly if you're sitting in the front row, it's quite obvious (to trained ears at least) that the sound is coming from above you instead of from behind the screen... Not so obvious from farther back.

Putting only the center speaker above the screen and L&R speakers on the sides doesn't sound like a good idea to me - I'd rather place them all on the same level vertically.

Posted by Harold Hallikainen (Member # 5405) on 01-16-2014, 09:15 AM:

Would a woven screen work?

No perforations and nearlybtransparent to sound.

Harold

Posted by Antti Nayha (Member # 4980) on 01-16-2014, 09:19 AM:

As much as I love woven screens, it wouldn't solve this issue:

quote: Edgar Prass
the screen would have to be even closer to the audience to accomodate speakers behind it. With room being that small I would prefer to have the screen as close to wall as possible to maximize the seating area.

Posted by Carsten Kurz (Member # 5396) on 01-16-2014, 11:00 AM:

It's a small arthouse screen. I think best would be to use microperf or woven screen and choose a low profile set of speakers. These are available and should be adequate.
25-30cm should be available, think e.g. JBL 3678, KCS S-1800. Alcons CR1+Alcons CB181SL (excellent, but expensive). http://qsccinema.com/news/qsc-announces-new-small-room-loudspeakers/

Sure this will not be THE 'Die Hard' location...

Phantom centering (two sets of speakers, above and below the screen) would be another (non optimal) option.

- Carsten

Posted by Steve Guttag (Member # 268) on 01-16-2014, 04:41 PM:

Be careful of the most company's small space speakers...eg the 3678...they really don't have a decent response. Yet speakers like the 4722 have a really good response and the passive crossover actually seems to match things well enough though I strongly prefer to biamp. I have not tried the new QSC small speakers but they are going to be quite expensive once you factor the price of Q-SYS into it all. QSC also has their single-15" 3 and 4-way (as well as 2-way) speakers that are going to sound good. Just remember, not all speakers are created equal...even from the same brand.

Definitely avoid having visible speakers...and use a microperf or woven screen and place the speakers behind it at all costs.

Posted by Jarod Reddig (Member # 6363) on 01-16-2014, 06:25 PM:

Do everything you can to get a acoustically transparent screen and place the LCR speakers behind it. You won't have to give up much space at all and the rewards from this type of setup versus speakers above or below the screen are huge.

Posted by Carsten Kurz (Member # 5396) on 01-17-2014, 05:14 AM:

Especially with audience sitting so close to the screen. Putting left/right at the sides of the screen may be just okay, but the center really should be behind the screen.

- Carsten